Struggling Emeral Crab

[wpeterson]

Struggling Emerald Crab

We added an Emerald Crab about 2 weeks ago to our tank. He was carefully drip acclimated over an hour or more and quite healthy. He's been making his way around our rockwork eating nuisance algae happily ever since.

This morning I found him on his back with his legs in the air, looking dead/dieing, but he still responded when I poked him with tweezers. I turned him right-side up and placed him back on the rockwork. He's not active, but appeared to grab on.

This is my 29gal mixed reef tank, which has been established for a year now.

Current Water Params:
Alk: 10 dkh
Ca: 460ppm
Mg: 1600ppm (deliberately raised to discourage hair algae)
Salinity: 1.025
pH: 8.3
Nitrate: 0
Phosphate: 0

No one else in the tank is showing signs of stress (SPS have good polyp extension, Rainbow BTA is open and bubbly). He spends most of his time in the top-half of the rockwork and I've seen no conflict or aggression with other tank mates.

Fish:
Pair of Percula Clowns, Yellow Headed Jawfish, Green Clown Goby

Inverts:
Scarlet Hermits, Anemone Shrimp, Peppermint Shrimp, Astrea Snails, Trochus Snails, Nassarius Snails, Cerith Snails, and Stomatella Snails

Any ideas what could be going wrong here? Aggression from some of the other inverts?

 

[MrX]

Maybe it's just getting ready to molt? Otherwise I don't have any ideas. I had some emerald's in my old 120G and a couple just disappeared. The shells were found, but they were empty. Never saw them again.

 

[wpeterson]

Maybe it's just getting ready to molt? Otherwise I don't have any ideas. I had some emerald's in my old 120G and a couple just disappeared. The shells were found, but they were empty. Never saw them again.

Thanks. That is my hope, as well. I'll be keeping an eye on him, but wanted to see if there's anything else we might be missing.

 

[focus]

Never been able to keep then since down sizing,in the 120 they had a long healthy life,they don't live long in my 40 breeder or the JBJ 28 I had set up. I think he's a goner seen those symptoms many times....

 

[wpeterson]

He was just molting. It took him most of the day, but he should be fine.

Sorry to bother you guys. The hermits and shrimp have very different molting behavior.